The role of the essential GTPase ObgE in regulating lipopolysaccharide synthesis in Escherichia coli.

During growth, cells need to synthesize and expand their envelope, a process that requires careful regulation. Here, we show that the GTPase ObgE of E. coli contributes to the regulation of lipopolysaccharide (LPS) synthesis, an essential component of the Gram-negative outer membrane.

Unveiling the Complexity of cis-Regulation Mechanisms in Kinases: A Comprehensive Analysis.

Protein cis-regulatory elements (CREs) are regions that modulate the activity of a protein through intramolecular interactions. Kinases, pivotal enzymes in numerous biological processes, often undergo regulatory control via inhibitory interactions in cis. This study delves into the mechanisms of cis regulation in kinases mediated by CREs, employing a combined structural and sequence analysis.

VIM-1-producing Enterobacter asburiae with mobile colistin resistance genes from wastewaters.

Background: Wastewaters are considered as important players in the spread of antimicrobial resistance, thus affecting the health of humans and animals. Here, we focused on wastewaters as a possible source of carbapenemase-producing Enterobacterales for the environment.

Methods: A total of 180 presumptive coliforms from hospital and municipal wastewaters, and a river in the Czech Republic were obtained by selective cultivation on meropenem-supplemented media and tested for presence of carbapenemase-encoding genes by PCR.

Sculpting conducting nanopore size and shape through de novo protein design.

Transmembrane β-barrels have considerable potential for a broad range of sensing applications. Current engineering approaches for nanopore sensors are limited to naturally occurring channels, which provide suboptimal starting points. By contrast, de novo protein design can in principle create an unlimited number of new nanopores with any desired properties.

Bactericidal effect of bacteria isolated from the marine sponges Hymeniacidon perlevis and Halichondria panicea against carbapenem-resistant Acinetobacter baumannii.

In this study, we evaluated the antimicrobial activity of bacteria isolated from the marine sponges Hymeniacidon perlevis and Halichondria panicea against seven Acinetobacter baumannii strains, the majority of which were clinically relevant carbapenem-resistant A. baumannii strains. We observed the inhibitory activity of 18 (out of 114) sponge-isolated bacterial strains against all A.

Fuzzy recognition by the prokaryotic transcription factor HigA2 from Vibrio cholerae.

Disordered protein sequences can exhibit different binding modes, ranging from well-ordered folding-upon-binding to highly dynamic fuzzy binding. The primary function of the intrinsically disordered region of the antitoxin HigA2 from Vibrio cholerae is to neutralize HigB2 toxin through ultra-high-affinity folding-upon-binding interaction. Here, we show that the same intrinsically disordered region can also mediate fuzzy interactions with its operator DNA and, through interplay with the folded helix-turn-helix domain, regulates transcription from the higBA2 operon.

Chronic spontaneous urticaria: Evidence of systemic microcirculatory changes.

Background: Chronic spontaneous urticaria (CSU) is a chronic inflammatory skin disease where activation of endothelial cells (ECs) at sites of skin lesions leads to increased blood flow, leakage of fluid into the skin, cellular infiltration, and vascular remodeling. To understand the disease duration and the sometimes vague systemic symptoms accompanying flares, the objective of this study was to examine if CSU comes with systemic vascular changes at the microcirculatory level.

Methods: We investigated CSU patients (n = 49) and healthy controls (HCs, n = 44) for microcirculatory differences by nailfold videocapillaroscopy (NVC) and for blood levels of the soluble EC biomarkers serum vascular endothelial growth factor (VEGF), soluble E-selectin, and stem cell factor (SCF).

Broad-Host Dissemination of Plasmids Coharboring the Operon for Fructooligosaccharide Metabolism with Antibiotic Resistance Genes.

The operon encoding short-chain fructooligosaccharide (scFOS) utilization enables bacteria of the family to grow and be sustained in environments where they would struggle to survive. Despite several cases of the detection of the operon in isolates of avian and equine origins, its global distribution in bacterial genomes remains unknown. The presence of the plasmid-harbored operon among resistant bacteria may promote the spread of antibiotic resistance.

The intracellular life of Acinetobacter baumannii.

Acinetobacter baumannii is a Gram-negative opportunistic bacterium responsible for nosocomial and community-acquired infections. This pathogen is globally disseminated and associated with high levels of antibiotic resistance, which makes it an important threat to human health. Recently, new evidence showed that several A.

Bypassing the Need for Cell Permeabilization: Nanobody CDR3 Peptide Improves Binding on Living Bacteria.

Membrane interaction constitutes to be an essential parameter in the mode of action of entities such as proteins, as well as cell-penetrating and antimicrobial peptides, resulting in noninvasive or lytic activities depending on the membrane compositions and interactions. Recently, a nanobody able to interact with the top priority, multidrug-resistant bacterial pathogen was discovered, although binding took place with fixed cells only. To potentially overcome this limitation, linear peptides corresponding to the complementarity-determining regions (CDR) were synthesized and fluorescently labeled.

Phenotypic Characterization and Heterogeneity among Modern Clinical Isolates of Acinetobacter baumannii.

Acinetobacter baumannii is an opportunistic pathogenic bacterium prioritized by WHO and CDC because of its increasing antibiotic resistance. Heterogeneity among strains represents the hallmark of A. baumannii bacteria.

Intrinsic protein disorder uncouples affinity from binding specificity.

Intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs) of proteins often function by molecular recognition, in which they undergo induced folding. Based on prior generalizations, the idea prevails in the IDP field that due to the entropic penalty of induced folding, the major functional advantage associated with this binding mode is "uncoupling" specificity from binding strength. Nevertheless, both weaker binding and high specificity of IDPs/IDRs rest on limited experimental observations, making these assumptions more speculations than evidence-supported facts.

Genomic Analysis of a Strain Collection Containing Multidrug-, Extensively Drug-, Pandrug-, and Carbapenem-Resistant Modern Clinical Isolates of Acinetobacter baumannii.

In this study, we characterize a new collection that comprises multidrug-resistant (MDR), extensively drug-resistant (XDR), pandrug-resistant (PDR), and carbapenem-resistant modern clinical isolates of Acinetobacter baumannii collected from hospitals through national microbiological surveillance in Belgium. Bacterial isolates ( = 43) were subjected to whole-genome sequencing (WGS), combining Illumina (MiSeq) and Nanopore (MinION) technologies, from which high-quality genomes (chromosome and plasmids) were assembled. Antimicrobial susceptibility testing was performed along with genome analyses, which identified intrinsic and acquired resistance determinants along with their genetic environments and vehicles.

Fitness effects of blaCTX-M-15-harbouring F2:A1:B- plasmids on their native Escherichia coli ST131 H30Rx hosts.

Objectives: To investigate the fitness effects of large blaCTX-M-15-harbouring F2:A1:B- plasmids on their native Escherichia coli ST131 H30Rx hosts.

Methods: We selected five E. coli ST131 H30Rx isolates of diverse origin, each carrying an F2:A1:B- plasmid with the blaCTX-M-15 gene.

Persistence and multi-ward dissemination of vancomycin-resistant Enterococcus faecium ST17 clone in hospital settings in Slovakia 2017-2020.

Objectives: Hospital vancomycin-resistant Enterococcus faecium (VREfm) were evaluated in term of resistance and phylogenetic relatedness to estimate the location and possible route of transmission of resistance determinants.

Methods: Hospital VREfm (n = 49) were collected in the northern part of Slovakia during 2017-2020. The collection was analysed for the presence of the van operon and 10 representatives were subjected to whole-genome sequencing using Illumina MiSeq platform.

gen. nov., sp. nov., Carrying Two Variants of Resistance Gene from Bacteroides fragilis, and gen. nov., sp. nov., Two Novel Genera Isolated from Chicken Caeca.

Three difficult-to-cultivate, strictly anaerobic strains, AN20, AN421, and AN502, were analyzed within a project studying possible probiotics for newly hatched chickens. Phylogenetic analyses showed that strains AN20, AN421, and AN502 formed two well-separated phylogenetic lineages in all phylogenetic and phylogenomic trees comprising members of the family . Comparison to reference genomes of type species Bacteroides fragilis NCTC 9343, Phocaeicola abscessus CCUG 55929, and Capsularis zoogleoformans ATCC 33285 showed low relatedness based on the calculated genome-to-genome distance and orthologous average nucleotide identity.

Antimicrobial Activity of a Repurposed Harmine-Derived Compound on Carbapenem-Resistant Clinical Isolates.

Objectives: The spread of antibiotic resistant bacteria is an important threat for human health. bacteria impose such a major issue, as multidrug- to pandrug-resistant strains have been isolated, rendering some infections untreatable. In this context, carbapenem-resistant bacteria were ranked as top priority by both WHO and CDC.

Scarless excision of an insertion sequence restores capsule production and virulence in Acinetobacter baumannii.

We identify a new mechanism mediating capsule production and virulence in the WHO and CDC priority ESKAPE pathogen Acinetobacter baumannii. Non-capsulated and avirulent bacteria can revert into a capsulated and virulent state upon scarless excision of an ISAba13 insertion sequence under stress conditions. Reversion events fully restore capsule production and in vivo virulence.

Cellular Chaperone Function of Intrinsically Disordered Dehydrin ERD14.

Disordered plant chaperones play key roles in helping plants survive in harsh conditions, and they are indispensable for seeds to remain viable. Aside from well-known and thoroughly characterized globular chaperone proteins, there are a number of intrinsically disordered proteins (IDPs) that can also serve as highly effective protecting agents in the cells. One of the largest groups of disordered chaperones is the group of dehydrins, proteins that are expressed at high levels under different abiotic stress conditions, such as drought, high temperature, or osmotic stress.

Efficient long-range conduction in cable bacteria through nickel protein wires.

Filamentous cable bacteria display long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on individual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating protein shell layer.

PED in 2021: a major update of the protein ensemble database for intrinsically disordered proteins.

The Protein Ensemble Database (PED) (https://proteinensemble.org), which holds structural ensembles of intrinsically disordered proteins (IDPs), has been significantly updated and upgraded since its last release in 2016. The new version, PED 4.

Discussions on the quality of antibodies are no reason to ban animal immunization.

Debates about the source of antibodies and their use are confusing two different issues. A ban on life immunization would have no repercussions on the quality of antibodies.